The lithium air battery is a battery using air (oxygen) as the cathode active material and has advantages such as being high in energy density and being easy to downsize and weight save. Thus, the lithium air battery is attracting attention as a high-capacity secondary battery which exceeds the lithium ion battery widely used at present.
Heretofore, there have been attempts of incorporating the function(s) of lithium ion battery to the lithium air battery in order to obtain a highly-functional lithium air battery. For example, the Patent Document 1 discloses a nonaqueous electrolyte air battery comprising a layer having at least oxygen reduction ability and a layer having at least lithium ion storage ability, in which the layer having the lithium ion storage ability contains an active material which has ability to store lithium ions of 2.0 V or more to 2.9 V or less (vs. Li).
This technique aims to improve the large-current discharge properties of the battery by providing a layer which functions as a cathode layer of the lithium ion battery (a layer which at least has lithium ion storage ability) in addition to a layer which functions as a cathode of the lithium air battery (a layer which at least has oxygen reduction ability). Thereby, even when the amount of air supplied to the lithium air battery is reduced in order to restrain water from entering the battery, the lithium ion battery functions complementary so that the large-current discharge properties of the battery is improved.    Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No. 2006-286414